Properties of the Number 81669

Eighty-One Thousand Six Hundred Sixty-Nine

Basics

Value: 81668 → 81669 → 81670

Parity: odd

Prime: No

Previous Prime: 81667

Next Prime: 81671

Digit Sum: 30

Digital Root: 3

Palindrome: No

Factorization: 3 × 7 × 3889

Divisors: 1, 3, 7, 21, 3889, 11667, 27223, 81669

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 10011111100000101

Octal: 237405

Duodecimal: 3B319

Hexadecimal: 13f05

Square: 6669825561

Square Root: 285.7778857784486

Classification

Fibonacci: No

Bell Number: No

Factorial Number: No

Regular Number: No

Perfect Number: No

Special

Kaprekar Constant: No

Munchausen Constant: No

Armstrong Number: No

Kaprekar Number: No

Catalan Number: No

Vampire Number: No

Taxicab Number: No

Super Prime: No

Friedman Number: No

Fermat Number: No

Cullen Number: No

OEIS Sequences

Array read by antidiagonals: A(n,k) is the number of nonnegative integer matrices with k columns and any number of distinct nonzero rows with column sums n. A331568

Number of nonnegative integer matrices with 2 columns and any number of distinct nonzero rows with column sums n. A331646

Expansion of exp(2x)+exp(x)BesselI₀(2x). A81669

Number of 3Xn 0..1 arrays with no 1 equal to more than two of its horizontal, diagonal and antidiagonal neighbors, with the exception of exactly two elements. A283786